From 3b9ff059d5b6db618440af2954262e68f4b02e87 Mon Sep 17 00:00:00 2001
From: Ignacio Van Droogenbroeck <64545348+xe-nvdk@users.noreply.github.com>
Date: Thu, 5 Nov 2026 08:56:32 -0600
Subject: [PATCH] docs(changelog): list the query completeness fields in 0.2.0
 (Arc#726)

---
 CHANGELOG.md | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ce989b5..9bbe9d6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -28,6 +28,14 @@ plus bug fixes and the first real HTTP-layer test coverage.
   - `tag_columns=` on `write_columnar`/`write_dataframe` and buffered writes,
     sent as msgpack `tag_keys`.
 - **Query path.**
+  - Result completeness (Arc#726): `QueryResponse.truncated` and
+    `truncation_reason` say Arc's stream failed part way, so `data` is missing
+    rows and must not be treated as the full result. `query()` returns them
+    rather than raising, so check `truncated` before using `data`.
+    `rows_capped` and `row_cap` say a governance row cap stopped the query:
+    the result is valid up to the cap. On Arrow, a truncated stream raises
+    `ArcQueryError` and the cap is in the schema metadata (`arc.rows_capped`,
+    `arc.row_cap`); on MessagePack, an incomplete body raises `ArcQueryError`.
   - `profile=True` on `query`/`query_msgpack`, returned as `QueryResponse.profile`.
   - `dictionary=`/`compression=` Arrow wire options.
   - `QueryResponse.query_id`, and `arc.query_id` in the Arrow schema metadata,